[PATCH v2 11/18] x86: merge csum_fold() for 32bit and 64bit

[Al Viro]

Identical.

Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
---
 arch/x86/include/asm/checksum.h    | 22 ++++++++++++++++++++++
 arch/x86/include/asm/checksum_32.h | 14 --------------
 arch/x86/include/asm/checksum_64.h | 18 ------------------
 3 files changed, 22 insertions(+), 32 deletions(-)

diff --git a/arch/x86/include/asm/checksum.h b/arch/x86/include/asm/checksum.h
index 6df6ece8a28e..eaa5dda09bee 100644
--- a/arch/x86/include/asm/checksum.h
+++ b/arch/x86/include/asm/checksum.h
@@ -1,13 +1,35 @@
 /* SPDX-License-Identifier: GPL-2.0 */
+#ifndef _ASM_X86_CHECKSUM_H
+#define _ASM_X86_CHECKSUM_H
 #ifdef CONFIG_GENERIC_CSUM
 # include <asm-generic/checksum.h>
 #else
 # define  _HAVE_ARCH_COPY_AND_CSUM_FROM_USER 1
 # define HAVE_CSUM_COPY_USER
 # define _HAVE_ARCH_CSUM_AND_COPY
+
+/**
+ * csum_fold - Fold and invert a 32bit checksum.
+ * sum: 32bit unfolded sum
+ *
+ * Fold a 32bit running checksum to 16bit and invert it. This is usually
+ * the last step before putting a checksum into a packet.
+ * Make sure not to mix with 64bit checksums.
+ */
+static inline __sum16 csum_fold(__wsum sum)
+{
+	asm("  addl %1,%0\n"
+	    "  adcl $0xffff,%0"
+	    : "=r" (sum)
+	    : "r" ((__force u32)sum << 16),
+	      "0" ((__force u32)sum & 0xffff0000));
+	return (__force __sum16)(~(__force u32)sum >> 16);
+}
+
 # ifdef CONFIG_X86_32
 #  include <asm/checksum_32.h>
 # else
 #  include <asm/checksum_64.h>
 # endif
 #endif
+#endif
diff --git a/arch/x86/include/asm/checksum_32.h b/arch/x86/include/asm/checksum_32.h
index 7570bdff7dea..4e96d0473f88 100644
--- a/arch/x86/include/asm/checksum_32.h
+++ b/arch/x86/include/asm/checksum_32.h
@@ -92,20 +92,6 @@ static inline __sum16 ip_fast_csum(const void *iph, unsigned int ihl)
 	return (__force __sum16)sum;
 }
 
-/*
- *	Fold a partial checksum
- */
-
-static inline __sum16 csum_fold(__wsum sum)
-{
-	asm("addl %1, %0		;\n"
-	    "adcl $0xffff, %0	;\n"
-	    : "=r" (sum)
-	    : "r" ((__force u32)sum << 16),
-	      "0" ((__force u32)sum & 0xffff0000));
-	return (__force __sum16)(~(__force u32)sum >> 16);
-}
-
 static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
 					__u32 len, __u8 proto,
 					__wsum sum)
diff --git a/arch/x86/include/asm/checksum_64.h b/arch/x86/include/asm/checksum_64.h
index 2bd75710eea1..d261b4124ca6 100644
--- a/arch/x86/include/asm/checksum_64.h
+++ b/arch/x86/include/asm/checksum_64.h
@@ -11,24 +11,6 @@
 #include <linux/compiler.h>
 #include <asm/byteorder.h>
 
-/**
- * csum_fold - Fold and invert a 32bit checksum.
- * sum: 32bit unfolded sum
- *
- * Fold a 32bit running checksum to 16bit and invert it. This is usually
- * the last step before putting a checksum into a packet.
- * Make sure not to mix with 64bit checksums.
- */
-static inline __sum16 csum_fold(__wsum sum)
-{
-	asm("  addl %1,%0\n"
-	    "  adcl $0xffff,%0"
-	    : "=r" (sum)
-	    : "r" ((__force u32)sum << 16),
-	      "0" ((__force u32)sum & 0xffff0000));
-	return (__force __sum16)(~(__force u32)sum >> 16);
-}
-
 /*
  *	This is a version of ip_compute_csum() optimized for IP headers,
  *	which always checksum on 4 octet boundaries.
-- 
2.39.2